ON CHEMICAL YIELDING PLANTS 



So it chances that the ancient calling of the 

 agriculturist is as essential to-day as it has always 

 been; and that it is necessary now as always here- 

 tofore to cultivate different varieties of plants in 

 order to gain the diverse products that man needs 

 or desires as food or as aids in the industries. 



The particular product that a hop vine grows, 

 and in the production of which it has an absolute 

 monopoly, is used, as everyone is aware, by the 

 brewer in the process of the manufacture of beer. 



He has been able to find no product that makes 

 a satisfactory substitute for the bitter principle 

 supplied by the lupulin of the hop. 



The particular place in which the hop vine 

 stores this bitter alkaloid, once it has manufac- 

 tured it, is the curious cone-like leafy seed-case 

 or envelope of the pistillate flower. Without doubt 

 the plant develops this bitter principle and stores 

 it there to give the seeds protection from the 

 depredations of animals. But whatever its pur- 

 pose, the bitter alkaloid provided by the hop was 

 discovered at an early date to have value for the 

 purposes of the brewer, and the hop vine continues 

 to be grown in large quantities solely for the 

 production of this alkaloid. 



The hop vine belongs to that somewhat 

 numerous tribe of plants that grow the pistillate 

 and staminate flowers on different vines. It is 



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